Mutant VAPB inclusions do not colocalize with mutant seipin inclusions. Primary cultured hippocampal neurons cotransfected with HA-VAPB-P56S and wild-type (A) S90L- (B), or N88L-mutant myc-tagged seipin constructs (C-F). Wild-type seipin shows a diffuse distribution throughout the cell body (A), while seipin-S90L and seipin-N88S accumulate in small inclusions (B-E) resembling mutant VAPB inclusions. However, seipin inclusions do not overlap with VAPB inclusions, and do not stain with antibody against ubiquitinated epitopes (FK2, C), VCP (D), derlin-1 (E) and BAP31 (F). Scale bar, 10 μm.